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NEW YORK STATE MUSEUM 



that go to complete the glenoid cavities of each shoulder joint. The 

 entire anterior margin of a scapula is devoted to the articular facet 

 for the coracoid. 



The glenoid cavity formed by the approximation of these two 

 bones is quite deep and extensive, and I find no os humero scapular e 

 present. Os furcula is of the broad U-shaped pattern. Superiorly 

 this bone presents for examination the great flattened ends that 

 articulate with the coracoids and scapulae on either side; these are 

 drawn out into rounded points behind to reach the latter, while a 

 limited smooth surface on the outer aspect of either limb comes in 

 contact with a similar surface on each of the former. All the 

 mesial surface of the os furcula is smooth and devoid of any points 

 of particular interest [pi. 13, fig. 28]. Externally and above, we 

 find the entrances to the great air passages, for they are more than 

 foramina, that lead into the bone. No hypocleidium projects from 

 the thoroughly united clavicles of these birds 'below, but a little ridge 

 occupies the usual site beneath and a characteristic tip projects from 

 in front in all of them. Behind, the borders are rounded ; in front, 

 they are sharpened and produced out to the point of the aforesaid 

 tip or anterior projection. With the scapular apparatus in position, 

 we find that the axis of the shafts of the coracoids is in line with 

 the long axis of the sternal body; that these bones diverge from 

 each other at an angle that is equal to the angle of the clavicular 

 fourchette. From behind their heads the articulated scapulae 

 spring out at nearly right angles, and pass backward parallel with 

 each other, to be deflected outward only as we near their posterior 

 points or extremities. After closing in the large " tendinal fora- 

 mina " by its broad superior dilatations, the furcula dips directly 

 backward to bring its lower arch into the recess of the anterior 

 concavity of the carina of the sternum, but it never touches this 

 bone at that point, and its near approach seems to vary for the 

 same species ; it is quite distant in a skeleton of the King vulture at 

 hand ; while in another it comes much nearer. 



In the vast majority of the diurnal Falconidae of this country, 

 and, no doubt, in those of the Old World too, the clavicular heads 

 present a much more intimate articulation with the superior ends 

 of the coracoids than we have just ascribed to the Cathartidae. 

 This arrangement is closely followed by Neophron, and, in short, 

 the entire scapular apparatus of this bird is indubitably stamped 

 with the well known characteristics that mark this arch among the 

 hawks and eagles. 



